Worldwide there are approximately 22 million persons currently living with HIV infection, and approximately 3 million individuals are newly infected each year. There are now more than 7,000 new HIV infections each day, of which over 1,000 occur in infants born to HIV-infected mothers. The vast majority of all new HIV infections are transmitted heterosexually, and increasing rates of infection of women during their reproductive years lead to growing rates of perinatal HIV infection. Over 90% of new HIV infections, and nearly all new infections of infants and young children, take place in developing countries where new antiviral drugs that enable effective treatment and prevention of HIV infection are not available. Development of a safe and effective HIV vaccine represents the best hope for containing the devastating spread of HIV throughout the world. However, progress towards a protective HIV vaccine has been limited by fundamental features of how HIV interact s with th e human immune system and the inability of traditional vaccine approaches to engender the type of strong and durable immune responses likely to be needed to protect from HIV infection. Realization of an effective HIV vaccine will probably require a better understanding of how to elicit potent immune responses against HIV and the development of new methods of vaccination. This project will strive to address both of theses needs. We will examine new strategies to enhance immune responses in hopes of enabling stronger, longer-lasting anti-HIV immunity. In addition, we will explore new methods of immunization, especially those that adapt available viral vaccines to express HIV components and that may be most relevant for children and adolescents. Our goal is to derive new approaches to immunize children and adolescents so that they are protected from HIV infection as they approach sexual maturity FUNDING Pediatric AIDS Foundation $682,500 1/01/98 -12/31/02 PUBLICATIONS NONE P51RR00165-38 1/1/1998 - 12/31/1998 Yerkes Regional Primate Research Center